The present invention relates to a process for sterilization, especially for the sterilization of packaging materials (and in particular plastic materials and materials having a plastic coating), by wetting with an active-chlorine-containing sterilizing solution.
Processes of this type are used, for example, in the sterilization of packaging for milk or other drinks or foodstuffs, where the packaging material is a web of plastic material or plastic-coated foil. In known processes, the packaging material is sterilized by an approximately 30% solution of hydrogen peroxide at a high temperature (about 90.degree. C.). Such a process should destroy all bacteria spores which could spoil the food or lead to food poisoning. However, the heating required for such a process is complex and expensive, and the subsequent elimination of the hydrogen peroxide, which is used in high concentration, may be dangerous for the operators. Also because of the high hydrogen peroxide concentration, there is the risk of dangerous residues remaining in the packaged foodstuff.
We have now discovered a reliable process for sterilizing the surfaces of packaging materials, which process will destroy bacterial spores at a relatively low temperature while allowing the sterilization solution to be handled without danger and without any undesirable residues remaining in the packaged product.